Optical Barrier for Microbiological Control after a Sterilization Process

Bruno Pereira de Oliveira, Kate Cristina Blanco, Javier A. Jurado, Vanderlei Salvador Bagnato

University of São Paulo, São Carlos Institute of Physics, São Carlos, São Paulo, Brazil

*Corresponding author: Kate Cristina Blanco. University of São Paulo, São Carlos Institute of Physics, São Carlos, São Paulo, Brazil. E-mail: blancokate@gmail.com

Published: June 16, 2017.  doi: 10.21103/Article7(2)_OA10


An optical barrier (OB) may eliminate the entrance of aerosol generated by clinical procedures in sterilization devices. The OB is a new alternative for sterilizing medical and dental instruments. The objective of the study was to evaluate the action of the OB on the entrance of bacteria into an autoclaving system and to correlate the time and distance of exposure. To test the configuration of the device, we used Escherichia coli. A lamp utilized in this instrument was low pressure with a wavelength around 254 nm. A homogenous distribution of light around the door was observed by the Inventor 2015 software. Microbiological tests showed efficient bacterial elimination at a distance of 8cm from OB. The results show that the use of the OB radiation for 30 minutes guarantees the non-entry of microorganisms into the sterilized environment. The use of the OB may be recommended to maintain the surface of sterile materials for long periods of time.

optical barrier ● bacteria ● UV light ● Escherichia coli ● biomedical device
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International Journal of Biomedicine. 2017;7(2):135-137. ©2017 International Medical Research and Development Corporation. All rights reserved.